Reptilia - Sauropterygia - Polycotylidae
Invalid subtaxa: Plesiosaurus ichthyospondylus Seeley 1869 [nomen vanum], Polycotylus ichthyospondylus Seeley 1869 [nomen vanum], Trinacromerum ichthyospondylus Seeley 1869 [nomen vanum], Trinacromerum latimanus Williston 1908 [nomen vanum]
Full reference: S. W. Williston. 1902. Restoration of Dolichorhynchops osborni, a new Cretaceous plesiosaur. Kansas University Science Bulletin 1(9):241-244
Parent taxon: Polycotylidae according to H. F. Ketchum and R. B. J. Benson 2010
Sister taxa: Ceraunosaurus, Edgarosaurus, Eopolycotylus, Georgiasaurus, Manemergus, Pahasapasaurus, Palmulainae, Palmulasaurinae, Palmulasaurus, Piratosaurus, Plesiopleurodon, Polycotyilnae, Polycotylinae, Sulcusuchus, Thililua, Trinacromerum
Subtaxa: Dolichorhynchops bonneri, Dolichorhynchops herschelensis, Dolichorhynchops osborni, Dolichorhynchops tropicensis
Ecology: aquatic carnivore